How to import a rigged model ?

Hi everyone,

I made a rigged mesh in Blender. It's a very simple mesh, with only three bones (root, left and right). The mesh represents two balls linked together by a plastic spring (it's a cat toy). I want to make them jiggle when the device moves (it's a mobile game), so I want to use this script :

http://wiki.unity3d.com/index.php?title=JiggleBone

The issue is : when I import my .fbx storing my rigged mesh, I can see in Unity the mesh and the three bones, but the bones doesn't seem to be connected to anything. When I move them, the vertex groups that are attached to them in Blender aren't impacted.

Is there anything I have forgotten to do when I imported my .fbx ?

Thanks for your help !